//
//  ProfileView+Provider.swift
//  Passepartout
//
//  Created by Davide De Rosa on 3/18/22.
//  Copyright (c) 2023 Davide De Rosa. All rights reserved.
//
//  https://github.com/passepartoutvpn
//
//  This file is part of Passepartout.
//
//  Passepartout is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  Passepartout is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with Passepartout.  If not, see <http://www.gnu.org/licenses/>.
//

import PassepartoutLibrary
import SwiftUI

extension ProfileView {
    struct ProviderSection: View, ProviderProfileAvailability {
        @ObservedObject var providerManager: ProviderManager

        @ObservedObject private var currentProfile: ObservableProfile

        @State private var isProviderLocationPresented = false

        @State private var isRefreshingInfrastructure = false

        var profile: Profile {
            currentProfile.value
        }

        init(currentProfile: ObservableProfile) {
            providerManager = .shared
            self.currentProfile = currentProfile
        }

        var body: some View {
            debugChanges()
            return Group {
                if isProviderProfileAvailable {
                    mainView
                } else {
                    EmptyView()
                }
            }
        }
    }
}

// MARK: -

private extension ProfileView.ProviderSection {

    @ViewBuilder
    var mainView: some View {
        Section {
            NavigationLink(isActive: $isProviderLocationPresented) {
                ProviderLocationView(
                    currentProfile: currentProfile,
                    isEditable: true,
                    isPresented: $isProviderLocationPresented
                )
            } label: {
                HStack {
                    Label(L10n.Provider.Location.title, systemImage: themeProviderLocationImage)
                    Spacer()
                    currentProviderCountryImage
                }
            }
        } header: {
            currentProviderFullName.map(Text.init)
        } footer: {
            currentProviderServerDescription.map(Text.init)
        }
        Section {
            Toggle(
                L10n.Profile.Items.RandomizesServer.caption,
                isOn: $currentProfile.value.providerRandomizesServer ?? false
            )
            Toggle(
                L10n.Profile.Items.VpnResolvesHostname.caption,
                isOn: $currentProfile.value.networkSettings.resolvesHostname
            )
        } footer: {
            Text(L10n.Profile.Sections.VpnResolvesHostname.footer)
                .xxxThemeTruncation()
        }
        Section {
            NavigationLink {
                ProviderPresetView(currentProfile: currentProfile)
            } label: {
                Label(L10n.Provider.Preset.title, systemImage: themeProviderPresetImage)
                    .withTrailingText(currentProviderPreset)
            }
            Button {
                refreshInfrastructure()
            } label: {
                Text(L10n.Profile.Items.Provider.Refresh.caption)
            }.withTrailingProgress(when: isRefreshingInfrastructure)
        } footer: {
            lastInfrastructureUpdate.map {
                Text(L10n.Profile.Sections.ProviderInfrastructure.footer($0))
            }
        }
    }

    var currentProviderFullName: String? {
        guard let name = profile.header.providerName else {
            assertionFailure("Provider name accessed but profile is not a provider (isPlaceholder? \(profile.isPlaceholder))")
            return nil
        }
        guard let metadata = providerManager.provider(withName: name) else {
            assertionFailure("Provider metadata not found")
            return nil
        }
        return metadata.fullName
    }

    var currentProviderServerDescription: String? {
        guard let server = profile.providerServer(providerManager) else {
            return nil
        }
        if currentProfile.value.providerRandomizesServer ?? false {
            return server.localizedDescription(style: .countryWithCategory(withCategory: true))
        } else {
            return server.localizedDescription(style: .longWithCategory(withCategory: true))
        }
    }

    var currentProviderCountryImage: Image? {
        guard let code = profile.providerServer(providerManager)?.countryCode else {
            return nil
        }
        return themeAssetsCountryImage(code).asAssetImage
    }

    var currentProviderPreset: String? {
        providerManager.localizedDescription(optionalStyle: .preset(profile: profile))
    }

    var lastInfrastructureUpdate: String? {
        providerManager.localizedDescription(optionalStyle: .infrastructureUpdate(profile: profile))
    }
}

// MARK: -

private extension ProfileView.ProviderSection {
    func refreshInfrastructure() {
        isRefreshingInfrastructure = true
        Task { @MainActor in
            try? await providerManager.fetchRemoteProviderPublisher(forProfile: profile).async()
            isRefreshingInfrastructure = false
        }
    }
}